Without limiting the scope of the invention, its background is described in connection with methods of manufacture and use of large hydrophobe surfactants and related compounds for oil recovery applications.
U.S. Pat. No. 4,842,776 issued to Schmidt et al. (1989) discloses Styrylaryloxy ether sulfonates of the formula:
in which either R1 denotes styryl and simultaneously R2 and R3 are identical or different and denote hydrogen or styryl, or R1 and R2 are nonidentical and each denote methyl or styryl and simultaneously R3 denotes hydrogen or styryl, x denotes a number from 2 to 20, and M denotes an ammonium or alkali metal cation. These compounds are suitable as surfactant auxiliaries in oil recovery.
WIPO Patent Application WO/2008/079855 (Raney and Schmidt, 2008) describes compositions and methods of treating a hydrocarbon containing formation, comprising: (a) providing a composition to at least a portion of the hydrocarbon containing formation, wherein the composition comprises a secondary alcohol derivative; and (b) allowing the composition to interact with hydrocarbons in the hydrocarbon containing formation. The invention further describes a composition produced from a hydrocarbon containing formation, comprising hydrocarbons from a hydrocarbon containing formation and a secondary alcohol derivative.
U.S. Patent Application No. 20090270281 (Steinbrenner et al., 2009) describes the use of a surfactant mixture comprising at least one surfactant having a hydrocarbon radical composed of from 12 to 30 carbon atoms and at least one co-surfactant having a branched hydrocarbon radical composed of from 6 to 11 carbon atoms for tertiary mineral oil extraction. According to the Steinbrenner invention, the surfactants (A) are used in a mixture with at least one co-surfactant (B) which has the general formula R2—O—(R3—O)n—R4, where the R2, R3 and R4 radicals and the number n are each defined as follows: n is from 2 to 20, R2 is a branched hydrocarbon radical which has from 6 to 11 carbon atoms and an average degree of branching of from 1 to 2.5, R3 are each independently an ethylene group or a propylene group, with the proviso that the ethylene and propylene groups—where both types of groups are present—may be arranged randomly, alternately or in block structure, R4 is hydrogen or a group selected from the group of —SO3H, —PO3H2, —R5—COOH, —R5—SO3H or —R5—PO3H2 or salts thereof, where R5 is a divalent hydrocarbon group having from 1 to 4 carbon atoms.